Laser scanning microscopes have conventionally acquired fluorescent images using fluorescent light emitted from a sample such as live cells after having excited a fluorescent substance in the sample, or light transmission images using transmitted light that passes through a sample, by radiating laser light onto the sample and scanning the sample with the laser light.
In addition, Patent Document 1 discloses a laser scanning microscope that controls irradiation of laser light so as to discontinue irradiation in the case the intensity of fluorescent light received is equal to or greater than a prescribed upper limit threshold value and in the case the intensity of fluorescent light received is equal to or less than a prescribed lower limit threshold value in order to inhibit damage (discoloration) of a sample by laser light.    Patent Document 1: Japanese Translation of PCT Application No. 2007-500880
However, in the laser scanning microscope described above, when fluorescent images are respectively acquired by fluorescent light of a plurality of wavelengths that has been excited by laser light of a certain single wavelength, suitable fluorescent images are unable to be acquired unless irradiation of laser light is suitably controlled.